论文部分内容阅读
目的:明确低氧预适应诱发胶质瘤细胞系SK-N-SH对BCNU的耐药,研究在低氧预适应的过程中一氧化氮合酶的作用及其机制。方法:用300μmol/L CoCl2预处理SK-N-SH细胞3小时,24小时后以BCNU刺激细胞,MTT法测定细胞增殖,流式细胞技术测定细胞的凋亡。RT-PCR技术检测神经型一氧化氮合酶和凋亡相关基因的表达情况。结果:300μmol/L CoCl2预处理可以明显增加细胞在BCNU条件下的增殖能力,减少凋亡。预适应可以上调神经型一氧化氮合酶的表达,同时可以上调凋亡抑制基因Bcl-2的表达,下调凋亡促进基因Apaf-1的表达。这些调节作用可被神经型一氧化氮合酶的抑制剂7-NI抑制。结论:300μmol/L CoCl2预处理SK-N-SH细胞3小时可以增加肿瘤细胞对BCNU的耐药作用。神经型一氧化氮合酶在预适应中可调节Bcl-2和Apaf-1基因的表达从而起到重要的作用。
OBJECTIVE: To determine whether hypoxia preconditioning induces SK-N-SH resistance to BCNU and to investigate the role of nitric oxide synthase and its mechanism during hypoxic preconditioning. Methods: SK-N-SH cells were pretreated with 300μmol / L CoCl2 for 3 hours, stimulated with BCNU 24 hours later, cell proliferation was measured by MTT assay, and apoptosis was measured by flow cytometry. RT-PCR was used to detect the expression of neuronal nitric oxide synthase and apoptosis related genes. Results: Pretreatment with 300 μmol / L CoCl2 significantly increased the proliferation of cells under BCNU and decreased the apoptosis. Preconditioning can upregulate the expression of neuronal nitric oxide synthase, upregulate the expression of Bcl-2, and down-regulate the expression of Apaf-1. These regulatory effects can be inhibited by the neuronal nitric oxide synthase inhibitor 7-NI. CONCLUSION: Pretreatment of SK-N-SH cells with 300μmol / L CoCl2 for 3 hours can increase the resistance of tumor cells to BCNU. Neuronal nitric oxide synthase plays an important role in the regulation of Bcl-2 and Apaf-1 gene expression in preconditioning.